The number of potholes on local roads in the UK has fallen by 27% since 2016, according to recently released statistics.
Data obtained under the Freedom of Information act by the Insurance Emporium shows that there were more than 780,000 potholes recorded on local authority managed roads in 2018, down from over 1M in 2016.
The fall in the number of pot holes follows an inquiry launched in August by the Commons transport select committee into the “plague of potholes”, which has led to a three-year high in vehicle breakdowns.
The data also names the City of Edinburgh as the local authority with the worst record for tackling potholes. It had 73 potholes per kilometre of managed road, the equivilant of one pothole every 13.7m. Dundee was second with 69 potholes per managed km of road.
Those with the lowest number of potholes were councils on the Shetland Islands and the Isles of Scilly with just 0.04 and 0.11 potholes respectively per managed km of road. This is likely due to hugely lower traffic levels.
The City of London has the highest per capita spend on pothole repairs at £60 per-head each year.
Nottingham University UK engineering professor Nicholas Thom said that potholes are not “inevitable” and that the use of cheaper materials in road surfacing is to blame.
“Potholes are not an inevitable fact of life,” said Thom. “They are caused by water that gets into the road surface and is then squeezed by the action of high tyre pressures, made worse by freezing and thawing. Very impermeable surfaces, such as hot rolled asphalt, are extremely pothole resistant but they are more expensive and less nice to drive on.”
He added: “More permeable surfaces, as permitted by Highways England and most local authorities, are cheaper and nicer to drive on – until they fall apart and form potholes. So the number of potholes per kilometre on a given authority’s roads depends not only on the repair budget, repair strategy, and the climate – frosts are bad news – but also on a historical policy choice, namely what surfacing materials to use. It is a choice that badly needs to be reviewed.”
A recent report from the RAC Foundation recently shows that some local authorities are using a new risk-based approach to dealing with potholes - so they can target road repairs at potholes putting road users at most risk almost.
Assessments take into account the width and depth of a pothole, the type of road it is on, the volume of traffic and the mix of road users. Experts have previously warned that poor quality roads with potholes could hold back the progress of autonomous vehicle development.
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